public int divisorSum(int n) {
        int divisor;
        int sum = 0;
        for(int i=1; i<=n;i++) {
            if(n%i == 0) {
                divisor = n/i;
                sum += divisor;
            }
        }

import math
class Calculator(AdvancedArithmetic):
    def divisorSum(self, n):
        sqrt = round(math.sqrt(n))
        divisors_sum = 0
        
        for i in range(1, sqrt+1):
            if n % i == 0:
                divisors_sum += i + n/i
        
        if (sqrt * sqrt == n):
            divisors_sum -= sqrt
            
        
        
        return int(divisors_sum)

class Calculator(AdvancedArithmetic):
    def divisorSum(self, n):
        s = 0
        for i in range(1, n+1):
            if n % i == 0:
                s+=i
        return s

return sum([i for i in range(1,int(n/2+1)) if n%i==0],n)

// Time: O(√n)

    int divisorSum(int n) {
        int sum = 0;
        if (n == 1) return 1;
        for(int i = 1; i * i <= n; i++){
            if( n % i == 0 ){
                if (i == n/i) sum +=  i;  //both factors are same
                else sum += i + n / i; 
            }
        }
        return sum;
    }
		
// Time: O(n)
			
    int divisorSum(int n) {
        int sum = 0;
        for(int i = 1; i <= n / 2; i++){
            if( n % i == 0 ) sum += i;
        }
        return sum + n;
    }